JPH04226736A - Plastic pipe - Google Patents

Abstract

PURPOSE: To provide an improved pipe produced from phenylene sulfide/ biphenylene sulfide copolymers and the manufacture thereof in which the improved pipe has greater flexibility than a pipe produced from normal PPS resin so as to achieve easy ductility. CONSTITUTION: Phenylene sulfide/biphenylene sulfide copolymers are prepared and the copolymers are formed into an essentially amorphous pipe by extrusion followed by rapid and uniform cooling to avoid pipe crystallization. Such an amorphous pipe is oriented by subsequent die extrusion uniaxially or biaxially.

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION This invention relates to plastics, particularly soft and flexible plastics. Poly(phenylene sulfide) resin (hereinafter referred to as P) is used to manufacture pipes.
It is known to use PS resins (sometimes referred to as PS resins). However, conventional PPS resins produce pipes that are crystalline and brittle. Commercial applications require non-brittle pipes that are more flexible and easier to stretch.

[0002] According to the present invention, a pipe is provided comprising a phenylene sulfide/biphenylene sulfide copolymer. According to another aspect of the invention, an amorphous pipe of PS/BPS copolymer is drawn by die extrusion to produce a flexible drawn pipe.

DETAILED DESCRIPTION OF THE INVENTION PS/BPS copolymers can be prepared by conventional methods. Copolymerization is described in US Pat. No. 3,919,177 by Campbell and Edmond
U.S. Patent No. 4,116,9 by S. and Scoggins
This can be carried out in a manner as extensively disclosed in the '47 specification. I hereby cite both disclosure documents for reference.

For example, a phenylene sulfide/biphenylene sulfide copolymer is prepared by first mixing at least one suitable sulfur source with at least one alkali metal carboxylate and at least one organic amide. . When using suitable sulfur sources other than alkali metal sulfides and alkali metal hydrosulfides, at least one base is also required. Similarly, it is preferred to use a base when using an alkali metal hydrosulfide as the sulfur source. The mixture is then heated, dehydrated, and then combined with two or more halogenated aromatic hydrocarbons for polymerization.

Phenylene sulfide/biphenylene
According to a highly preferred method of making sulfide copolymers, an aqueous solution of sodium hydroxide is first mixed with an aqueous solution of sodium bisulfide (NaSH), sodium acetate, and N
-Methyl-2-pyrrolidone (NMP). The mixture is then heated, dehydrated, and combined with para-dichlorobenzene (p-DCB), 1,2,4-trichlorobenzene (TCB), and 4,4'-dibromobiphenyl.

[0006] Generally, 4,4' used during the polymerization process
-The amount of dibromobiphenyl is between 1 mole percent and 1
5 mole percent (based on p-DCB and 4,4'-dibromobiphenyl charges). Preferably, this amount ranges from 3 mole percent to 10 mole percent, and more preferably, this amount is about 4 to 8 mole percent.

Generally, 1, 2,
The amount of 4-trichlorobenzene ranges from 0.05 to 0.8 mole percent (based on the p-DCB and 4,4'-dibromobiphenyl charges). Preferably,
This amount ranges from 0.1 to 0.6 mole percent, and more preferably, this amount ranges from 0.2 mole percent to 0.4 mole percent.

The temperature at which the polymerization can be carried out can vary over a wide range, but is generally from about 230°C to about 45°C.
It may be within the range of 0°C. Reaction time is about 10 minutes to about 3
It may be within a range of days, preferably from about 1 hour to about 8 hours. The pressure required is sufficient to effectively maintain the halogenated aromatic hydrocarbon and organic amide within the liquid phase and retain the sulfur source therein. Preferably, the polymerization reaction mixture is heated to about 230°C and held for about 2 hours, then heated to about 265°C and held for about 3 hours.
Hold time.

The phenylene sulfide/biphenylene sulfide copolymers prepared for use in the present invention can be prepared by conventional procedures such as filtering the polymer and then washing with water, or diluting the reaction mixture with water. The polymer can then be separated from the reaction mixture by filtration, washing with water, or the like. Preferably, at the end of the polymerization time, deionized water is added to the reactor to cool the contents to about 100°C and filtered. The polymer is then slurried with room temperature deionized water, filtered, slurried twice with hot (175° C.) deionized water, and then dried.

The copolymers prepared for use in the present invention have a melt viscosity measured as melt flow using a 5 kg weight at 316°C in accordance with ASTM D-1238 that It will have a suitable value for extrusion. Generally, a suitable melt flow is about 10g/1
Between 0 minutes and about 100 g/10 minutes, preferably 30
It will be somewhere between 70g/10min and 70g/10min.

The resulting polymer is then ready for extrusion into pipes. Preferably, the resulting polymer is pelletized using any extrusion equipment capable of reaching extrusion temperatures and then dried before being extruded into pipes. Generally, pelletization is carried out from about 280°C to about 340°C.
It is carried out using extrusion equipment with die temperatures in the range of .degree. Preferably, the die temperature is from about 300°C to about 3
It is in the range of 20°C. Generally, the pellets are dried at a temperature of about 150° C. for about 2 hours before being extruded into a pipe.

In accordance with the present invention, the PS/BPS copolymer is extruded into pipes. It is essential that the profile to be molded be approximately cylindrical, and preferably essentially cylindrical.

[0013] Generally, the PS/BPS copolymer is extruded into pipe using any extruder, die, quench equipment, and take-off equipment suitable for producing the amorphous pipe products of the present invention. . The equipment must be capable of reaching extrusion temperatures in the range of about 280 DEG C. to about 340 DEG C. and rapidly and uniformly quench the extruded pipe to avoid crystallization of the polymer. Preferably, the equipment is capable of reaching extrusion temperatures ranging from about 300°C to about 310°C. Generally, the pipe is quenched either by water spray from around the die opening or by means of a water bath. Preferably, the hot pipe is quenched by extruding it directly from the pipe mold into a water bath containing cooling water. Pipe withdrawal speeds will vary widely depending on the equipment used, pipe diameter, and desired wall thickness. This speed lies between 25 cm/min and 100 cm/min or more. The wall thickness of the pipe may vary depending on the ability of the quench system to cool the pipe to prevent polymer crystallization and the desired final drawn pipe wall thickness. in general,
The wall thickness of the amorphous pipe will be about 2 mm to about 6 mm. The outside diameter of the pipe will be selected based on the effective size of the pipe die available, the dimensions of the die extrusion, and the requirements for the drawn pipe.

After extrusion, the pipe of the present invention is essentially amorphous. The density of the pipe is preferably about 1.30g/
cc to about 1.32 g/cc. More preferably, the density is about 1.31-1.32 g/cc. For many applications, levels of additives such as carbon black, antioxidants, UV stabilizers or pigments may affect pipe density without adversely affecting pipe formation or drawing. It can exist in

In one embodiment of the invention, the amorphous pipe is then molecularly oriented. "Molecular orientation" means a preferred alignment of a certain axis or plane of a molecule with respect to a given axis or plane. This molecular orientation causes significant changes in the polymer's strength, elongation, elastic modulus, impact resistance, and other values.

In one embodiment of the invention, the amorphous pipe is oriented by subsequent die extrusion. This subsequent die extrusion can stretch or stretch the polymer uniaxially or biaxially at elevated temperatures.
It can be carried out with any die extrusion equipment.

[0017] Of course, all extrusions, in the case of the drawn PS/BPS copolymer pipes of the present invention, necessarily involve one die in the broadest sense, including the formation of the pipe precursor. “Die extrusion” refers to the subsequent die shaping (die
shaping) in which the copolymer pipe at the orientation temperature is stretched radially and/or longitudinally, and the general term "extrusion"
It is distinguished from Preferably, it is stretched simultaneously in both the radial and longitudinal directions to provide biaxial stretching.

"Orientation temperature" means the temperature at which the amorphous pipe is reheated so that it becomes (stretched) oriented. Generally, this temperature is near or above the glass transition temperature (Tg) of the polymer.

Preferably, the die extrusion apparatus is operated at a temperature in the range of about 80°C to about 115°C. More preferably,
The die extrusion temperature ranges from about 85°C to about 110°C.

Generally, the take-off speed for die extrusion equipment ranges from about 0.1 cm/min to about 100 cm/min. Preferably, the take-off speed is from about 0.5 cm/min to about 50 c
m/min range. Generally, the machine direction, or machine direction, stretch ratio is within the range of about 1.5 times to about 8 times. Preferably, it is in the range of about 2 times to about 7 times. Generally, the hoop direction, or transverse, stretch ratio ranges from about 1.5 times to about 4 times. Preferably, it is within the range of about 2 times to about 3 times. It is desirable that no significant amount of crystallization occur during this die extrusion step.

The wall thickness of the drawn copolymer pipe of the present invention varies over a wide range depending on the wall thickness of the starting amorphous pipe and the draw ratio chosen for drawing. It will generally range from about 0.1 mm to about 3 mm, preferably from 0.2 mm to 2 mm.

FIG. 1 is a diagram outlining a preferred process for making PS/BPS copolymer pipes. First, the PS/BPS copolymer is prepared by any conventional method. Secondly, the copolymer obtained above is pelletized using any extrusion equipment capable of reaching extrusion temperatures and then dried. . Third, the copolymer pellets are extruded into pipes using any extrusion equipment capable of reaching extrusion temperatures. Fourth, the pipe is quenched by any method that allows rapid and uniform quenching to avoid crystallization of the pipe. Finally, the obtained amorphous pipe is drawn by subsequent die extrusion.

FIG. 2 is a cross-sectional view of a die extrusion apparatus capable of uniaxially stretching or elongating polymers under elevated temperatures. In a preferred embodiment of the invention,
Originally amorphous pipe made of PS/BPS copolymer 1
0 is passed between a heated die 12 and a mandrel 14 to produce a die-drawn pipe 16. The resulting die drawn pipe 16 is stretched, thus imparting molecular orientation to the pipe in the machine direction.

FIG. 3 is a cross-sectional view of a die extrusion apparatus capable of drawing or elongating under elevated temperatures so as to obtain biaxially molecularly oriented pipes. In a preferred embodiment of the invention, the essentially amorphous pipe 10a of PS/BPS copolymer is heated through a heated die 12.
a and the mandrel 14a and die drawing (orientation)
A pipe 16a is manufactured. The resulting die drawn pipe 16a is stretched in the machine direction, or machine direction, and is also stretched in the hoop direction, or transverse direction.

The pipe made of the amorphous copolymer of the present invention is translucent and non-brittle. It is suitable for use at moderate temperatures where good chemical resistance is required and where direct visual observation of material flow is useful to detect where flow problems or plugging may exist. It can be used to transport chemicals and slurries (below the crystallization temperature). The stretched pipe is flexible and can be used as a flame retardant insulating wrapper or support for electrical wiring. After stretching, it can be cut lengthwise and expanded to form a stretched film, which can also be used for electrical and electronic applications.

[0026]

EXAMPLES The examples described below are provided to explain the invention more specifically, and should not be considered as unduly limiting the scope of the invention.

In the following examples, melt flow (M
F) The value has been partially revised to allow for the use of 5 minutes of preheating.
STM D-1238 method (conditions: 316℃/5kg
) was determined. The melt flow value of the polymer is g
/10 minutes. Density values were determined using gradient tube densitometry and are expressed in g/cc. Annealed specimens for density measurements were prepared by crushing a small piece of pipe (including the entire cross section) and placing it in a forced air oven for 2 hours.
Prepared by annealing at 00°C for 15 minutes. Differential scanning calorimeter (DSC) values of the glass transition temperature (Tg) and crystalline melting point (Tm) peaks were measured for samples premelted and quenched in a Perkin-Elmer DSC-2C differential scanning calorimeter equipped with a data station. It was decided from.

Pipe samples were cut to desired length and tested either as prepared or after annealing at 200° C. for 30 minutes in a forced air oven. The value of rapid burst pressure expressed in psig is the pressure that is applied gradually to the inside of a 48 cm long pipe sample with plugs at both ends until the pipe finally breaks, or the maximum pressure of the test equipment. It was determined from the pressure when it reached (approximately 1500 psi).

The physical properties of the die extruded pipe are:
This was determined by cutting dog bone-shaped specimens in both the vertical and horizontal directions and testing them with an Instron tensile tester.

American Hoechst Co.
rp. The 4,4'-dibromobiphenyl monomer purchased from , was 98.5% pure, with the remainder of the monomer being monobromobiphenyl. Standard Chl
orine Chemical Co. , Inc. Meta-dichlorobenzene (meta-DCB) purchased from
of which 42.8% is meta-DCB, 47.2% is para-DCB, and the remaining 7.7% is ortho-DCB.
B (% is based on weight).

Die extrusion of the pipe samples was carried out in a die extrusion apparatus as shown in FIG. 3, which is the presently preferred embodiment. The die extrusion apparatus consisted of an electrically heated die 12a with the same die diameter as the pipe 10a. A mandrel 14a was supported inside the pipe 10a, the diameter of which increased downstream of the die diameter and just behind the die diameter. The longitudinal (machine direction) drawing was controlled by the speed at which the drawn pipe 16a was withdrawn from the die 12a. Lateral direction(
The draw in the hoop direction) was controlled by the diameter of the mandrel 14a after the die 12a. A heated chamber surrounded the die extruder. Die extrusion of the pipe was started by shaping the pipe end to mandrel dimensions in a heated oil bath. The pipe was pulled through the die at a slow speed until some stretching occurred, then the speed was increased to the desired speed.

Polymerization The polymers used in the following examples were polymerized as described above. An aqueous solution of sodium hydroxide was mixed with an aqueous sodium bisulfide (NaSH) solution, sodium acetate, and NMP. This mixture was heated, dehydrated, and then combined with two or more halogenated aromatic hydrocarbons for polymerization. All polymers were prepared using para-dichlorobenzene (p-DCB) and 1,2,4-trichlorobenzene (TCB). In some experiments, part of the p-DCB was replaced with another monomer to investigate the effect of various different comonomers. Polymers 5, 6, 7 are 4,4′-dibromobiphenyl (p-
6 of the total charge of DCB and 4,4′-dibromobiphenyl.
(mol percent). Polymer 8,9
, 10 is meta-dichlorobenzene (m-DCB) (m-
8 mol percent of total DCB and p-DCB charge)
Prepared using A sufficient amount of the m-DCB/p-DCB monomer mixture was used to give the specified m-DCB content. Each polymerization mixture was heated to about 230°C and
hold at that temperature for an hour, then heat to about 265°C;
It was held for about 3 hours.

In the case of Polymer 1, at the end of the polymerization time the polymerization mixture was concentrated at about 265° C. by partial evaporation of the solvent. Approximately 24 liters of concentrated PPS slurry
The solvent was further evaporated off at 0° C., washed with room temperature water and filtered. The polymer was slurried using hot water (190°C), filtered, and dried to obtain Polymer 1.

For other polymers 2-10, deionized water was added to the reactor at the end of the polymerization time, the contents were cooled to about 100° C., and filtered. Polymers 2-10 were slurried with deionized water at room temperature, filtered, and washed with heat (17
5°C) slurried twice with deionized water, filtered,
Dry.

[0035]

EXAMPLE 1 This example illustrates the difficulties in manufacturing die extruded PPS pipe using polymers outside the scope of the present invention. p- as a halogenated aromatic hydrocarbon
Four PPS samples were prepared using only DCB and TCB. TCB expressed as mole percent of p-DCB
The addition levels are shown in Table 1 along with the melt flow (MF) values of the polymers.

[0036]
Table 1
PPS polymer

T.C.B., M.
F, Polymer
mole % g
/10 minutes 1
0.22
50 2
0.275
21
3 0.275
28
4 0.20
44

The four polymers were sieved through a 325 mesh sieve for Polymers 1 and 4, a 200 mesh sieve for Polymer 3, and a 200 mesh sieve for Polymer 2 at a melting temperature of about 300-330°C.
In each case, pellets were formed without using a sieve. Each pellet was dried at 125-150° C. for several hours and extruded into pipes using a 38 mm diameter Davis-Standard extruder equipped with a pipe die. Internal air pressure (1
4 to 22 psig), the open end of the pipe was plugged and a pipe with an outer diameter of 33 mm was extruded. Water spray from around the die opening was used to cool the pipes made from Polymers 1 and 2. In the case of pipes from polymers 3 and 4, a water bath was added to make cooling the pipes more effective. The pipe samples are described in Table 2.

Polymer 1 was extruded at a die temperature of about 305° C. and a take-off speed of about 580 mm/min to produce a pipe with a wall thickness of about 3 mm. Similar pipes subsequently produced under similar conditions had a density of 1.360 g/cc and 1.366 g/cc after annealing at 200°C for 15 minutes.
It was cc. The relatively small change in density upon annealing and the initially opaque appearance of the pipe both indicate that the extruded pipe was already largely crystallized. The bursting strength of the pipe was high. Subsequent attempts to draw pipe from Polymer 1 by die extrusion were unsuccessful.

[0039]
Table 2
PPS pipe


pipe
pellet pipe
rupture
MF,
Thickness, density,
Strength, polymer g/1
0 minutes mm
g/cc psig
1 50
3 1
．． 3601 17001 2
ND2
1 1.327
ND2 3
28 3.
9 1.346
>15003 4
ND2 33
1.336 >15
003 Note. ) 1 Measurements based on similar pipe samples made subsequently. 2 Not Determined. 3 The sample did not burst at the specified pressure.

Polymer 2 was extruded into a pipe at a drawing speed of about 152 cm/min, with a wall thickness of about 1 mm and a density of 1.327.
g/cc pipe was manufactured. Pipe density, transparency,
This indicates an essentially amorphous pipe in terms of its flexibility and flexibility. This pipe is about 86~9
It could be easily die extruded at a temperature of 0° C. and a take-off speed of up to about 40 cm/min. However, the wall thickness of the die-extruded pipe is limited to a maximum stretching ratio of approximately 1.8 times in the longitudinal direction and approximately 2.1 times in the horizontal direction.
Under the draw conditions up to double, it was only about 0.2 to 0.4 mm.

Pipe extrusion from polymers 3 and 4 is
A water bath approximately 152 cm long containing cold (approximately 24° C.) water was used. The hot pipe was extruded directly from the pipe die into a water bath. The pipe from Polymer 3 was extruded using a take-off speed of 47 cm/min, and the extruded pipe had a density of 1.346 g/cc (Table 2) and a wall thickness of 3.9 m.
It was m. Polymer 4 was extruded into a pipe at a take-up speed of 58 cm/min, and the wall thickness of the extruded pipe was 3
The density was 1.336 g/cc in mm. Judging from their density and opaque appearance, these pipe samples were highly crystalline and would probably have been unsuitable for die extrusion.

The results for this example show that ordinary PP
Pipe extruded from S shows rapid crystallization when the pipe wall thickness is relatively thick (approximately 3-4 mm). Thin walled (approximately 1 mm) pipe can be quenched in an essentially amorphous state and then die extruded. However, the thin wall thickness of the starting pipe material limits the wall thickness of the die extruded product. In addition, rapid draw-off stretching during pipe extrusion limits the amount of stretching possible during die extrusion.

[0043]

Example 2 This example demonstrates the preparation of die extruded pipe according to the present invention from copolymers designated Polymers 5,6,7. Polymers 5, 6, and 7 are 6 moles
% (based on the total charge of p-DCB and 4,4'-dibromobiphenyl) of 4,4'-dibromobiphenyl and the amounts of 1,2,4-trichlorobenzene shown in Table 3. Polymerization was carried out as described above. The melt flow values of the resulting polymers ranged from 3 to 71 g/10 min. DSC for PPS similar to polymer 1 (
Differential scanning calorimeter) value, Tg=94℃, Tm=273℃
The DSC results for polymers 5, 6, and 7 shown in Table 3 show that these polymers have higher T
g value and lower Tm value.

[0044]
Table 3 Phenylene sulfide/biphenylene sulfide copolymer
TCB,1
MF, Tg,
Tm, polymer mol% g/10 min
℃ ℃ 5 0.4
3
101 251 6
0.4
28
97 261 7
0.2
71 97
255 Note. ) 1 mole % of the total charge of p-DCB and 4,4'-dibromobiphenyl.

Polymers 6 and 7 were pelletized on a 38 mm diameter single screw extruder using a 200 mesh screen placed in the breaker plate and a die temperature of 316°C. The pellets from Polymers 6 and 7 were dried at 150° C. for 2 hours and then extruded into pipes using the same extruder and pipe mold as described in Example 1, and a pipe quench bath. Polymer 6 is 313
It was extruded into pipe using a die temperature of 0.degree. C. and an internal air pressure of 13 psig. Polymer 7 was extruded into pipe using a die temperature of 293° C. and an internal air pressure of 16 psig. For both extrusions, the pipe take-off speed used was 58 cm.
/min, and a wall thickness of about 3 mm was obtained.

Pipe products from Polymers 6 and 7 are described in Table 4. Based on the low density and clean cross-section, the pipes from Polymer 7 were essentially amorphous. The pipe obtained from Polymer 6 had a slightly higher density than the pipe from Polymer 7, with evidence of crystalline regions in the center of the cross section of the pipe. It is clear that during the extrusion of the pipe from Polymer 6, the temperature of the water bath increased, which delayed the cooling of the pipe and consequently allowed a small trace of crystallization to occur in the center of the pipe wall. be. The annealed pipe from Polymer 7 had slightly reduced burst strength compared to the extruded raw pipe.

[0047]
Table 4 Pipe of phenylene sulfide/biphenylene sulfide copolymer

pipe
pellet
MF,
Density, bursting strength, polymer g/10 min
Anneal g/cc
psig 6
27 None 1.328
>14001
Yes 1.3
50 >12001 7 53
None 1.3
14 >14001
Yes 1.3
48 1075 Note. ) 1 The sample did not rupture at the specified pressure.

Pipe of Polymer 7 was prepared using the same extruder and pipe die described in Example I at a die temperature of 86.
Die extrusion was performed at 110° C. and at a take-off speed of 0.5 to 42 cm/min. The stretching ratio in the machine direction or machine direction was as high as 6.3 times, and the stretching ratio in the hoop direction or transverse direction reached a maximum of about 2.4 times. Test results for several of the Polymer 7 die extruded pipe samples are shown in Table 5. Various physical properties were obtained depending on the draw conditions. The die extruded sample has a density of 1.3
16-1.317 g/cc, indicating that no significant crystallization occurred during the die extrusion process.

[0049]
Table 5
Pipe die extrusion of polymer 7


Tensile strength Draw Stretching ratio Wall thickness, m
m MPa
Die speed, horizontal vertical
Horizontal Vertical
Horizontal vertical temperature, °C mm/min Direction Direction Direction
Direction Direction 105 5 2.41
2.04 0.7-0.8 0.9-1
．． 0 81 71 103
5 2.40 2.8
6 0.6-0.7 0.65-0.7
60 68 110
18 2.39 6.30 0
．． 3-0.3 0.3-0.5 4
8 103

The results of this example show that the pipe extruded from the PS/BPS copolymer is rapidly cooled to an essentially amorphous state even when the pipe wall thickness is relatively thick (approximately 3-4 mm). It shows that it can be made into a state. These essentially amorphous pipes obtained can then be drawn (pulled) into strong biaxially oriented pipes with reasonably balanced properties in the machine and transverse directions. can.

[0051]

[Example 3] This example shows meta-dichlorobenzene (
meta-DCB) and para-dichlorobenzene (p-D
CB) is illustrated. These copolymers are outside the scope of this invention and are unsuitable for extrusion into relatively thick walled, amorphous pipes that are die extrudable.

The three copolymers, Polymers 8, 9, and 10, were combined with meta-DCB in an amount corresponding to 8 mole percent of the total charge of m-DCB and p-DCB as shown in Table 6. It was prepared using the added amount of 1,2,4-trichlorobenzene. Melt flow values for Polymers 8, 9 and 10 ranged from 17 to 84 g/10 min. The differential scanning calorimetry Tg and Tm values for Polymers 8, 9, and 10 are lower than those for PPS similar to Polymer 1 (Tg = 94°C, Tm = 273°C).

[0053]
Table 6
Meta-DCB/para-DCB copolymer
TCB,1
MF, T
g Tm polymer
Mol % g/10 min
℃ ℃ 8 0.5
17
82 232 9
0.4
34
84 231 10
0.4
84 81
234 note. ) 1 m-DCB and p-DCB in mole % relative to the total charge.

Polymers 8, 9, and 10 were extruded in a 38 mm diameter single screw using a 200 mesh screen placed in a breaker plate and die temperatures of 320° C., 316° C., and 304° C., respectively. Pelletized on the machine. Pellets from polymers 8, 9, 10 are 15
Dry at 0°C for 2 hours, then the pellets were prepared in Example 1.
They were extruded into pipes using the same extruder and pipe die as described in , along with a water bath for cooling the pipes. 16p
The internal air pressure of sig is 310℃, 299℃, 3 respectively.
Pipes were extruded from polymers 8, 9, and 10 using a die temperature of 0.4°C. In all extrusions, a pipe take-off speed of 58 cm/min was used, resulting in a pipe wall thickness of approximately 3 mm.

Pipe products from polymers 8, 9, and 10 are described in Table 7. Although the extruded pipe samples all had nearly the same density (1.329-1.331 g/cc), the pipe from Polymer 8 had signs of crystallization in the center of the pipe wall. On the other hand, the other two pipe samples from polymers 9 and 10 had clean cross sections. Samples of annealed pipes from polymers 8, 9, and 10 each had approximately the same density (1.3
61-1.362 g/cc), polymer 8,9,
It showed a lower bursting strength than the original pipe sample from 10.

[0056]
Table 7
Meta-DCB/para-DCB copolymer pipe


pipe pellets
MF,
density,
Bursting strength, polymer g
/10 minutes Anneal 1
g/cc psig
8 12.5
None 1.3
31 >14002

Yes 1.361
880 9
28 None
1.329 >14002

Yes 1
．． 361 920 10
56
None 1.329
>14002
Yes
1.362 Note. ) 1 Annealed at 200°C for 15 minutes for density measurement and 30 minutes for burst test. 2 The sample did not burst at the specified pressure.

Attempts to die extrude the pipe product of this sample were unsuccessful due to cracking in the machine direction of the pipe.

The results of this example demonstrate that copolymers made using meta-DCB and para-DCB can be die extruded into pipes with clean cross sections by die extrusion. However, the pipe obtained thereby cannot be drawn by subsequent die extrusion without longitudinal cracking of the pipe.

The results of the foregoing examples show that pipes extruded from PS/BPS copolymers are rapidly cooled to an essentially amorphous state even when the pipe wall thickness is relatively thick (3-4 mm). It has been shown that it can be stretched by subsequent die extrusion. Pipes extruded from other PS polymers and copolymers have relatively thin walls (approximately 1 m
m) cannot be stretched by subsequent die extrusion.

The examples and data described so far indicate that phenylene sulfide/biphenylene sulfide copolymers are less brittle than pipes extruded from other arylene sulfide homopolymers and copolymers.
Therefore, it can be seen that it is suitable for producing extruded pipes that are more flexible and easy to stretch.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a preferred process for manufacturing pipes using PS/BPS copolymers.

FIG. 2 is a longitudinal cross-sectional view of a die extrusion device that can be used to uniaxially stretch a pipe.

FIG. 3 is a longitudinal cross-sectional view of a die extrusion apparatus that can be used to biaxially stretch pipe.

[Explanation of symbols]

10 Essentially amorphous pipe 10a made of PS/BPS copolymer Essentially amorphous pipe 12 made of PS/BPS copolymer Heated die 12a Heated die 14 Mandrel 14a Mandrel 16 Die Stretched pipe 16a Die-stretched pipe

Claims (33)

[Claims] [Claim 1] A plastic pipe made of phenylene sulfide/biphenylene sulfide copolymer. [Claim 2] The copolymer is para-dichlorobenzene,
A pipe according to claim 1, which is produced from monomers consisting of 4,4'-dibromobiphenyl and 1,2,4-trichlorobenzene. 3. The amount of 4,4'-dibromobiphenyl present during the polymerization process is equal to that of para-dichlorobenzene and 4,4'-dibromobiphenyl.
, about 1 based on the charge of 4'-dibromobiphenyl.
3. The pipe of claim 2, in the range of mole percent to about 15 mole percent. 4. The amount of 4,4'-dibromobiphenyl present during the polymerization process is equal to that of para-dichlorobenzene and 4,4'-dibromobiphenyl.
, based on the charge of 4'-dibromobiphenyl, about 3
4. The pipe of claim 3, in the range of mole percent to about 10 mole percent. 5. The 1,2,4- present during the polymerization process.
5. The amount of trichlorobenzene is in the range of about 0.05 mole percent to about 0.8 mole percent based on the charges of para-dichlorobenzene and 4,4'-dibromobiphenyl. One pipe listed. 6. The amount of 4,4'-dibromobiphenyl present during the polymerization process is equal to that of para-dichlorobenzene and 4,4'-dibromobiphenyl.
, based on the charge of 4'-dibromobiphenyl.
The amount of 1,2,4-trichlorobenzene present during the polymerization process ranges from mole percent to about 8 mole percent, and the amount of 1,2,4-trichlorobenzene present during the polymerization process is between para-dichlorobenzene and 4,4'-
6. A pipe according to any one of claims 2 to 5, in the range of about 0.2 mole percent to about 0.4 mole percent, based on the dibromobiphenyl charge. 7. A pipe according to claim 1, wherein the copolymer is essentially amorphous. 8. The pipe according to claim 1, wherein the copolymer of the pipe has molecular orientation. 9. The pipe of claim 8, wherein the copolymer of the pipe is biaxially oriented. [Claim 10] The wall thickness of the pipe is about 2 mm to about 6 mm.
10. A pipe according to any one of claims 1 to 9. 11. A plastic made of a copolymer of phenylene sulfide and biphenylene formed into an essentially amorphous pipe by extrusion and then rapidly and uniformly quenched to avoid crystallization of the pipe. Method of manufacturing pipes. 12. The copolymers used are para-dichlorobenzene, 4,4'-dibromobiphenyl and 1,2
12. A method according to claim 11, prepared by polymerizing a monomer system consisting of , 4-trichlorobenzene. 13. 4,4'- used during polymerization treatment
13. The method of claim 12, wherein the amount of dibromobiphenylene ranges from about 1 mole percent to about 15 mole percent based on the charges of para-dichlorobenzene and 4,4'-dibromobiphenyl. 14. 4,4'- used during polymerization treatment
14. The method of claim 13, wherein the amount of dibromobiphenyl ranges from about 3 mole percent to about 10 mole percent based on the charges of para-dichlorobenzene and 4,4'-dibromobiphenyl. 15. 4,4'- used during polymerization treatment
15. The method of claim 14, wherein the amount of dibromobiphenyl ranges from about 4 mole percent to about 8 mole percent based on the charges of para-dichlorobenzene and 4,4'-dibromobiphenyl. 16. 1, 2, 4 used during polymerization treatment
- trichlorobenzene is in the range of about 0.05 mole percent to about 0.8 mole percent based on the charges of para-dichlorobenzene and 4,4'-dibromobiphenyl. The method described in one of the following. 17. 1, 2, 4 used during polymerization treatment
17. The method of claim 16, wherein the amount of -trichlorobenzene ranges from about 0.1 mole percent to about 0.6 mole percent based on the charges of para-dichlorobenzene and 4,4'-dibromobiphenyl. 18. 1, 2, 4 used during polymerization treatment
18. The method of claim 17, wherein the amount of -trichlorobenzene is in the range of about 0.2 mole percent to about 0.4 mole percent based on the charges of para-dichlorobenzene and 4,4'-dibromobiphenyl. 19. The extrusion is performed at a temperature of about 280°C to about 340°C.
19. A method according to any one of claims 11 to 18, carried out using extrusion means at a temperature in the range of . 20. The extrusion is performed at a temperature of about 300°C to about 310°C.
20. A method according to claim 19, carried out using extrusion means at a temperature within the range of . 21. The pipe has a speed of about 25 cm/min to about 10 cm/min.
Claims 11 to 20, wherein the pipe is extruded to a wall thickness in the range of about 2 mm to about 6 mm at a pipe take-off speed in the range of 0 cm/min.
The method described in any one of the following. 22. A method according to claim 11, wherein the amorphous pipe is then biaxially stretched by subsequent die extrusion. 23. An extrusion in which the subsequent extrusion can stretch the amorphous pipe longitudinally and stretch it transversely at elevated temperatures such that the amorphous pipe is biaxially stretched. 23. The method of claim 22, which is carried out using means. 24. The extrusion means has a temperature of about 80°C to about 11°C.
24. A method according to claim 23, operated at a temperature within the range of 5<0>C. 25. The extrusion means has a temperature of about 85°C to about 11°C.
25. A method according to claim 24, operated at a temperature within the range of 0<0>C. 26. The subsequent die extrusion is about 0.1
26. A method according to any one of claims 23 to 25, carried out at a pipe take-off speed in the range from cm/min to about 100 cm/min. Claim 27: The pipe drawing speed is approximately 0.5 cm.
27. The method of claim 26, wherein the rate is in the range of 50 cm/min to about 50 cm/min. 28. A method according to any one of claims 23 to 27, wherein the axial stretch ratio of the subsequent die extrusion is in the range of 1.5 times to about 8 times. 29. The method of claim 28, wherein the longitudinal stretch ratio of the subsequent die extrusion ranges from about 2 times to about 7 times. 30. The method of any one of claims 23 to 29, wherein the lateral stretch ratio of the subsequent die extrusion ranges from about 1.5 times to about 4 times. 31. The stretching ratio in the lateral direction is about 2 times to about 3 times.
31. The method of claim 30, wherein: 32. A method according to claim 22, wherein the pipe is heated to a temperature corresponding to at least the glass transition temperature of the copolymer before mechanically stretching the pipe. 33. a) pelletizing the copolymer using a first extrusion means at a temperature within the range of about 300°C to about 320°C, and subsequently pelletizing the copolymer as described above. b) forming the copolymer of the pellets so dried into an essentially amorphous pipe using a second extrusion means; c) forming the copolymer of the pellets so formed into an essentially amorphous pipe; 33. A method according to any one of claims 11 to 32, comprising the steps of: drawing the crystalline pipe by subsequent die extrusion with a third extrusion means.